Stroker pistons with 2.0 crank ?

[95g-s-x]

This is purely out of curiosity, but what would displacement and compression ratio be for the following combination:

-2.0l block
-2.0l crank
-2.0l rods
-8.5:1 stroker pistons

Edit:

Based on the calculators i found online (assuming I entered the right #'s):

Displacement still: 2.0
Comp Ratio: 5.9:1

Does this look right?

 

[e85_4g63]

The compression ratio (static) or if you did a compression test (in psi)? The piston would sit 3mm down in the bore, which would cause SERIOUS issues. This will not work if that's what your getting at.

According to Manley (there 8.5:1 stroker pistons use a 22cc dished piston) the compression ration with that combo on a 150mm rod, 88mm stroke, .051 compressed head gasket (MLS), std deck height, 85.5mm bore (.020 over) is 6.6:1 static compression

http://www.csgnetwork.com/compcalc.html

^ CR calculator I used..

 

[95g-s-x]

Wouldn't the piston sit 6mm down in the bore since the pin position is moved up 6mm on the piston?

That is the same one I used

 

[viperlp01]

Yes the pistons would sit 6mm down in the bore. Even if you got 156mm rods(to compensate for the wrist pin) your compression ratio would be stupid low. You just need to get your self a 100mm stroke crank if you want to use those pistons.

 

[95g-s-x]

Yes the pistons would sit 6mm down in the bore. Even if you got 156mm rods(to compensate for the wrist pin) your compression ratio would be stupid low. You just need to get your self a 100mm stroke crank if you want to use those pistons.

It is just a hypothetical.

The effects of running such a low cr (6.0:1) would be very poor off boost power, but wouldn't you be able to run much higher boost (as long as your afr was in check) without detonating?

 

[viperlp01]

I run 30psi with a 10:1 compression ratio stroker. Is that low boost.

The car would be dog ass slow. You wouldn't even be able to spool a turbo worth while enough to give you the amount of boost(air flow) needed to make the car somewhat fast.... Just guessing you want to run gas, stick to at least the 6 bolt piston. My brothers 2g with a 6 bolt bottom end runs 30psi on his evo 16g on pump gas(7.8:1).

 

[e85_4g63]

6mm is correct.. I need sleep, ignore my previous post (Homer Simpson - DOUHHH)

 

[95g-s-x]

I run 30psi with a 10:1 compression ratio stroker. Is that low boost.

The car would be dog ass slow. You wouldn't even be able to spool a turbo worth while enough to give you the amount of boost(air flow) needed to make the car somewhat fast.... Just guessing you want to run gas, stick to at least the 6 bolt piston. My brothers 2g with a 6 bolt bottom end runs 30psi on his evo 16g on pump gas(7.8:1).

Good point! I never thought about not being able to spool the damn turbo. Again, I was just curious as to the effects. I have a bunch of spare parts laying around in my shop, and was looking at them, and thought...hmm.

It wouldn't have been anything i would put in my vehicles, both have built engines anyhow and I am very happy with their performance.

 

[viperlp01]

All you need is a 100mm crank and your set. I am using pistons not necessarily designed for the stroker set up. You have a good start for thinking outside the box.

 

[95g-s-x]

All you need is a 100mm crank and your set. I am using pistons not necessarily designed for the stroker set up. You have a good start for thinking outside the box.

I have a 2.3l stroker in my awd. These are just extra parts i has laying around. I suppose I could pick up another 4g64 crank and build a spare just incase mine takes a shit.

 

[talonDSMerr]

Yes the pistons would sit 6mm down in the bore. Even if you got 156mm rods(to compensate for the wrist pin) your compression ratio would be stupid low. You just need to get your self a 100mm stroke crank if you want to use those pistons.

Wait... the 156mm rods would move the stroker pistons back to the top of the cylinder wouldn't they? And should give the same compression ratio as you would using 150mm rods with a 100mm crank.

156mm rods used with the 88mm crankshaft and 2.3 stroker pistons is how people build the long rod 2.0L. The rod ratio of that motor is 1.77 compared to 1.5 of the conventional 2.3L stroker, which helps reduce side-loading forces that the piston exerts on the cylinder walls, and also reduces max piston velocity. Good for revving the motor to higher RPMs.

 

[viperlp01]

Wait... the 156mm rods would move the stroker pistons back to the top of the cylinder wouldn't they? And should give the same compression ratio as you would using 150mm rods with a 100mm crank.

156mm rods used with the 88mm crankshaft and 2.3 stroker pistons is how people build the long rod 2.0L. The rod ratio of that motor is 1.77 compared to 1.5 of the conventional 2.3L stroker, which helps reduce side-loading forces that the piston exerts on the cylinder walls, and also reduces max piston velocity. Good for revving the motor to higher RPMs.

No the compression ratio would not be the same if you used 156mm rods. A 8.5:1 stroker engine uses a -22cc volume dome, A same compression ratio long rod engine uses a -12cc dome volume. Using stroker pistons in a long rod engine would net you low compression. My estimation is around 7.5:1

 

[talonDSMerr]

Aha, I didn't take the piston dome volume into account. You're right, I crunched the numbers really quick and compression ratio would be right around 7.5:1.

 

[bryanwheat]

You are actually going to be 12mm below the top of the cylinder with 2.3 pistons and a 88 mm crank. With those pistons and a 100mm crank you will be at the top, no subtract 88 from 100 and you will be at 12 mm below the top of the cylinder.

 

[95g-s-x]

You are actually going to be 12mm below the top of the cylinder with 2.3 pistons and a 88 mm crank. With those pistons and a 100mm crank you will be at the top, no subtract 88 from 100 and you will be at 12 mm below the top of the cylinder.

Incorrect....the only change is in the stroker piston....the pin bore is moved up the piston 6mm, effectively lowering the top of the piston 6mm.

You are forgetting that w/ a 100mm crank, you only get 6mm more travel in each direction...up and down

 

[bryanwheat]

Actually after thinking about it for a second you are right, the stroke is from top to bottom of the cylinder. Regardless this engine would run like absolute crap. It might even have problems starting.